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Lynnfield Makes its Long Awaited Debut

Lynnfield Makes its Long Awaited Debut

Meet Lynnfield, Intel's latest processors that have been on the upcoming horizon for the longest time. The mainstream successor to Intel's Core 2 platform is based on the same 45nm Nehalem CPU microarchitecture as the Core i7 and it has finally arrived after being pushed back from its original July launch date. Much has been speculated about reasons for the delay of Lynnfield to the last quarter of 2009, though the general economic malaise certainly hasn't helped Intel's cause. In any case, we fancy that there should significant pent-up demand for new mainstream processors, what with Windows 7 launching next month.

Physically, these mainstream Lynnfield chips are smaller overall than the current Bloomfield Core i7 models in the market despite having slightly more transistors. The packaging is the reason for the size shrink. With the processor's much lower pin, it doesn't make economical sense to continue using the more expensive LGA1366 socket and its platform. As such the Lynnfield processors use a new socket, LGA1156 coupled with a new platform (which we'll touch upon quite shortly). While they are Nehalem architecture based and have common characteristics like a similar amount of L2 and L3 cache, there have been some significant changes under the hood. Firstly, the integrated tri-channel memory controller has been reduced to a more conventional dual-channel controller that should be adequate for most mainstream users.

Then there's the addition of an integrated PCIe graphics controller with 16 lanes of PCIe 2.0, removing another functionality from the motherboard chipset and bringing it into the processor. Of course, with its mainstream emphasis, some things had to go and the QuickPath Interconnect (QPI) links on the Bloomfield has been removed. One of Intel's older technologies, Direct Media Interface (DMI) is used instead to communicate with the chipset. Along with these changes, the cost of manufacturing has been lowered sufficiently for Intel to price them in the US$200 to US$600 range.

And it will be a new chipset that's doing the talking. Intel's P55 Express chipset, a new single chip design that does away with the North/Southbridge divide is currently the only one supporting the LGA1156 socket. We have previewed some of these P55 motherboards, like the ASUS P7P55 EVO, , the Gigabyte P55-UD6 and the MSI P55-GD80 and we'll be talking more about the Intel DP55KG reference board in a while.

Back to Lynnfield, Intel will be introducing three models this year, with more to follow in 2010. These processors are divided into two series, which is where the branding jargon gets confusing. First, there's the Core i5-750, with a nominal clock speed of 2.67GHz. The other Lynnfield processors however use the Core i7 moniker, the Core i7-870 and i7-860, clocked at 2.93GHz and 2.80GHz respectively.

In case you're wondering, there's a very important reason for this. The lower 700 series will not have HyperThreading as a feature, hence you can expect a maximum of four logical cores. The Core i7 800 series meanwhile will have HyperThreading onboard, though you can choose to disable it in the BIOS. The table below lists some of the important details about these available models:

Processor Model

Clock Speed

Max Turbo Frequency

L3 Cache

Cores/Threads

Direct Media Interface

Max TDP (W)

Retail Price (1K units)

Availability

Core i7-870

2.93GHz

3.60GHz

8MB

4/8

4.8GT/s

95W

~US$555

Now

Core i7-860

2.80GHz

3.46GHz

4/8

~US$285

Core i5-750

2.66GHz

3.20GHz

4/4

~US$199

As you may have noticed from the table, these Lynnfield processors have a Max Turbo Frequency column, which is probably the most significant change from Bloomfield. If you can remember, the Core i7 introduced this feature with the Bloomfield Core i7, where the processor will automatically ramp up the clock speed (increase in the multiplier) when fewer cores are being taxed. Lynnfield brings an enhanced version of this, which we shall elaborate next.